Post on 16-Dec-2015
transcript
Muscular System
The body system that covers, shapes, and supports the skeletal tissue
It contracts and moves various parts of the body
Muscle
600 muscles 40% of body’s weight Fibrous tissue that have the ability to stretch
and contract according to the demands of the body’s movements
Striated Muscles
Skeletal or voluntary muscles– Legs, arms, face etc.
Striped What we work over and are concerned about Attached to the bones and are controlled by
will– Create heat and energy for the body during
muscle contractions– Assist in maintaining posture– Protect some internal organs
Nonstriated Muscles
Involuntary, visceral– Diaphragm etc.
Smooth (not striped)Function automatically, without
conscious will, without thought or control – Found in internal organs of digestive and
respiratory systems
Origin
Part of the muscle that does not move Fixed attachment to a bone or ligament Direction of movement is from the insertion of
the muscle to the origin of the muscle
Muscle tissue can be stimulated by:
Massage Electrical current Light rays Dry heat Moist heat Nerve impulses Chemicals
Muscles of the scalp
Epicranius – broad muscle that covers the top of the skull– Occipitalis – back of the head
draws the scalp backward
– Frontalis – front of headmuscle that raises the eyebrowsDraws the scalp forwardCauses wrinkles across the forehead
Muscles of the ear
Auricularis superior – – Muscle above the ear that draws the ear
upwardAuricularis Anterior –
– Muscle in front of the ear that draws the ear forward
Auricularis Posterior – – Muscle behind the ear that draws the ear
backward
Muscle of Mastication (chewing)
Masseter – – Long broad muscle on the sides of the
chin - in front of the ear, to aid in chewingTemporalis –
– Muscle on sides of head above the ear and behind the eyes to aid the masseter in chewing
Muscles of the Neck
Platysma – – Broad muscle extending from the chest
and shoulder muscles to the side of the chin
– Responsible for lowering the lower jaw and lip
Sternocleidomastoideus – – Muscle of the neck that lowers and rotates
the head
Muscles of the Eyebrow
Corrugator – – located beneath the frontalis and
orbicularis oculi – Draws the eyebrow down– Wrinkles the forehead vertically
Orbicularis oculi –– Ring of muscle of the eye socket– Enables you to close your eyes
Muscles of the Nose
Procerus– Covers the bridge of the nose– Lowers the eyebrows– Causes wrinkles across the bridge of the
noseOther –
– Nasal muscles contract and expand the opening of the nostrils
Muscles of the Mouth
Mentalis– Elevates the lower lip– Raises and wrinkles the skin of the chin
Orbicularis Oris– Flat band around the mouth– Compresses, contracts, puckers and
wrinkles the lips - kissing
Risorius– Muscle that draws the corner of the mouth
out and back as in grinningTriangularis
– Muscle extending alongside the chin– Pulls down the corner of the mouth
Zygomaticus – Muscles extending from the zygomatic
bone to the angle of the mouth– Elevate the lip as in laughing
Muscles that attach the arms to the body
Latissimus Dorsi– Broad, flat superficial muscle covering the
back of the neck and upper and middle region of the back
– Controlling the shoulder blade and the swinging movements of the arm
Pectoralis major/pectoralis minor– Muscles of the chest that assist the
swinging movements of the armSerratus Anterior
– Muscle of the chest that assists in breathing and in raising the arm
Trapezius– Muscle that covers the back of the neck
and upper and middle region of the back– Rotates and controls swinging movements
of the arm
Muscles of the Shoulder and Arm
Biceps– Two (2) headed muscle– Muscle producing the contour of the front
and inner side of the upper arm– Lift the forearm– Flex elbow– Turn the palms outward
Deltoids– Large triangular muscle covering the
shoulder joint– Allows the arm to extend outward and to
the side of the body
Triceps– Three (3) headed muscle– Large muscle that covers the entire back
of the upper arm– Extends the forearm
Forearm muscles
Extensors– Muscles that straighten the wrist, hand,
and fingers to form a straight lineFlexors
– Extensor muscles of the wrist– Involved in bending the wrist
Pronators– Muscle that turn the hand inward so that
the palm faces downwardSupinators
– Muscle of the forearm that rotates the radius outward and the palm upward
Muscles of the Hand
Abductors– Muscle that separate the fingers
Adductors– Muscles at the base of each finger that
draw fingers togetherOpponent muscles
– Muscles in the palm that act to bring the thumb toward the fingers
Muscles of the Lower Leg and Foot
Extensor Digitorum Longus– Bends the foot up and extends the toes
Tibialis Anterior– Covers the front of the shin– Bends the foot upward and inward
Peroneus Longus– Covers the outer side of the calf– Inverts the foot– Turns it outward
Peroneus Brevis– Originates in the lower surface of the fibula– Bends the foot down and out
Gastrocnemius – Attached to the lower rear surface of the
heel– Pulls the foot down
Soleus– Originates in the upper portion of the fibula – Bends the foot down
Muscles of the Foot
Extensors Digitorum BrevisAbductor HallucisFlexor BrevisAbductor
– Muscles move the toes and help maintain balance while walking and standing